Machine tools, dedicated to a specific function, e.g. a table saw, are well known, each such machine tool being a stationary tool and having a base or leg structure which supports it on a work shop floor. Many of the functions performed by such machine tools can also be performed by hand-held portable power tools, e.g. a portable circular saw. Hand-held power tools are considerably less expensive than stationary machine tools and occupy considerably less storage space, but in general do not readily provide the same degree of accuracy as stationary machine tools.